This paper seeks to optimize parameters, reduce the cost of desulphurization and the consumption of operation about KR pretreatment of hot metal at the Stainless Steel Company, Baosteel Group. Based on the theoretical analysis of physical chemistry in metallurgy, simulation experiments of the KR desulphurization of hot metal were conducted in a laboratory and the composition of the desulphurization was optimized, by means of chemical analysis, DSC, SEM and EDS. The water modeling displays the fluid flow characteristics of KR desulphurization. Combination of the techniques and production at the Stainless Steel Company, Baosteel Group, the optimized parameters of the process are put forward. This paper seeks to optimize parameters, reduce the cost of desulphization and the consumption of operation about KR pretreatment of hot metal at the Stainless Steel Company, Baosteel Group. Based on the theoretical analysis of physical chemistry in metallurgy, simulation experiments of the KR desulfurization of hot metal were conducted in a laboratory and the composition of the desulphization was optimized, by means of chemical analysis, DSC, SEM and EDS. The water modeling displays the fluid flow characteristics of KR desulfurization. Combination of the techniques and production at the Stainless Steel Company, Baosteel Group, the optimized parameters of the process are put forward.